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/*
* Copyright (c) 2003, 2015, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* @test
* @bug 4530538
* @summary Basic unit test of mbean.getThreadCount()
* mbean.getTotalStartedThreadCount()
* mbean.getPeakThreadCount()
* mbean.getDaemonThreadCount()
* @author Alexei Guibadoulline
*
* @run main ThreadCounts
*/
import java.lang.management.*;
public class ThreadCounts {
static final int DAEMON_THREADS = 21;
static final int USER_THREADS_1 = 11;
static final int USER_THREADS_2 = 9;
static final int USER_THREADS = USER_THREADS_1 + USER_THREADS_2;
static final int ALL_THREADS = DAEMON_THREADS + USER_THREADS;
private static volatile boolean live[] = new boolean[ALL_THREADS];
private ThreadMXBean mbean = ManagementFactory.getThreadMXBean();
private static boolean testFailed = false;
// barrier for threads communication
private static Barrier barrier = new Barrier(DAEMON_THREADS);
public static void main(String argv[]) {
ThreadCounts test = new ThreadCounts();
Thread allThreads[] = new Thread[ALL_THREADS];
// Start DAEMON_THREADS threads and wait to be sure they all are alive
barrier.set(DAEMON_THREADS);
for (int i = 0; i < DAEMON_THREADS; i++) {
live[i] = true;
allThreads[i] = new MyThread(i);
allThreads[i].setDaemon(true);
allThreads[i].start();
}
// wait until all threads have started.
barrier.await();
System.out.println("Number of daemon threads added = " +
DAEMON_THREADS);
// Check mbean now
if ( (!test.checkCount (DAEMON_THREADS)) ||
(!test.checkCreated(DAEMON_THREADS)) ||
(!test.checkPeak (DAEMON_THREADS)) ||
(!test.checkDaemon (DAEMON_THREADS))
)
testFailed = true;
// Start USER_THREADS_1 threads and wait to be sure they all are alive
barrier.set(USER_THREADS_1);
for (int i = DAEMON_THREADS; i < DAEMON_THREADS + USER_THREADS_1; i++) {
live[i] = true;
allThreads[i] = new MyThread(i);
allThreads[i].setDaemon(false);
allThreads[i].start();
}
// wait until user1 threads have started.
barrier.await();
System.out.println("Number of threads added = " +
USER_THREADS_1);
// Check mbean now
if ( (!test.checkCount (DAEMON_THREADS + USER_THREADS_1)) ||
(!test.checkCreated(DAEMON_THREADS + USER_THREADS_1)) ||
(!test.checkPeak (DAEMON_THREADS + USER_THREADS_1)) ||
(!test.checkDaemon (DAEMON_THREADS))
)
testFailed = true;
// Stop daemon threads and wait to be sure they all are dead
barrier.set(DAEMON_THREADS);
for (int i = 0; i < DAEMON_THREADS; i++) {
live[i] = false;
}
// wait until daemon threads terminated.
barrier.await();
System.out.println("Daemon threads terminated.");
// Check mbean now
if ( (!test.checkCount (USER_THREADS_1)) ||
(!test.checkCreated(DAEMON_THREADS + USER_THREADS_1)) ||
(!test.checkPeak (DAEMON_THREADS + USER_THREADS_1)) ||
(!test.checkDaemon (0))
)
testFailed = true;
// Start USER_THREADS_2 threads and wait to be sure they all are alive
barrier.set(USER_THREADS_2);
for (int i = DAEMON_THREADS + USER_THREADS_1; i < ALL_THREADS; i++) {
live[i] = true;
allThreads[i] = new MyThread(i);
allThreads[i].setDaemon(false);
allThreads[i].start();
}
// wait until user2 threads have started.
barrier.await();
System.out.println("Number of threads added = " +
USER_THREADS_2);
// Check mbean now
if ( (!test.checkCount (USER_THREADS_1 + USER_THREADS_2)) ||
(!test.checkCreated(ALL_THREADS)) ||
(!test.checkPeak (DAEMON_THREADS + USER_THREADS_1)) ||
(!test.checkDaemon (0))
)
testFailed = true;
// Stop user1 threads and wait to be sure they all are dead
barrier.set(USER_THREADS_1);
for (int i = DAEMON_THREADS; i < DAEMON_THREADS + USER_THREADS_1; i++) {
live[i] = false;
}
// wait until user1 threads terminated.
barrier.await();
System.out.println("Number of threads terminated = " +
USER_THREADS_1);
// Check mbean now
if ( (!test.checkCount (USER_THREADS_2)) ||
(!test.checkCreated(ALL_THREADS)) ||
(!test.checkPeak (DAEMON_THREADS + USER_THREADS_1)) ||
(!test.checkDaemon (0))
)
testFailed = true;
// Stop user2 threads and wait to be sure they all are dead
barrier.set(USER_THREADS_2);
for (int i = DAEMON_THREADS + USER_THREADS_1; i < ALL_THREADS; i++) {
live[i] = false;
}
// wait until user2 threads terminated.
barrier.await();
System.out.println("Number of threads terminated = " +
USER_THREADS_2);
// Check mbean now
if ( (!test.checkCount (0)) ||
(!test.checkCreated(ALL_THREADS)) ||
(!test.checkPeak (DAEMON_THREADS + USER_THREADS_1)) ||
(!test.checkDaemon (0))
)
testFailed = true;
if (testFailed)
throw new RuntimeException("TEST FAILED.");
System.out.println("Test passed.");
}
// Nobody knows how many threads are in the JVM in the exact moment. The
// only thing to check for sure is minimal number of threads alive (or
// created) in the application
private boolean checkCount(long min) {
long result = mbean.getThreadCount();
if (result < min) {
System.err.println("TEST FAILED: " +
"Minimal number of live threads is " +
min +
". ThreadMXBean.getThreadCount() returned " +
result);
return false;
}
return true;
}
private boolean checkCreated(long min) {
long result = mbean.getTotalStartedThreadCount();
if (result < min) {
System.err.println("TEST FAILED: " +
"Minimal number of created threads is " +
min +
". ThreadMXBean.getTotalStartedThreadCount() "+
"returned " + result);
return false;
}
return true;
}
private boolean checkPeak(long min) {
long result = mbean.getPeakThreadCount();
if (result < min) {
System.err.println("TEST FAILED: " +
"Minimal peak thread count is " +
min +
". ThreadMXBean.getPeakThreadCount() "+
"returned " + result);
return false;
}
return true;
}
private boolean checkDaemon(long min) {
long result = mbean.getDaemonThreadCount();
if (result < min) {
System.err.println("TEST FAILED: " +
"Minimal number of daemon thread count is " +
min +
"ThreadMXBean.getDaemonThreadCount() returned "
+ result);
return false;
}
return true;
}
// The MyThread thread lives as long as correspondent live[i] value is true
private static class MyThread extends Thread {
int id;
MyThread(int id) {
this.id = id;
}
public void run() {
// signal started
barrier.signal();
while (live[id]) {
try {
sleep(100);
} catch (InterruptedException e) {
System.out.println("Unexpected exception is thrown.");
e.printStackTrace(System.out);
testFailed = true;
}
}
// signal about to exit
barrier.signal();
}
}
}
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